> | Lab 5.4.3: Migrating RIP to IGRP - Overview Estimated time: 30 min. Objectives: Verify the routing protocols are working properly Check routing table and interpret network entries Check for static routes and remove them if necessary Compare RIP to IGRP based on administrative distance Convert a RIP-based router network to IGRP Background: In this lab you will work with two dynamic interior routing protocols - Router Information Protocol (RIP) and Interior Gateway Routing Protocol (IGRP). Routing protocols are used by routers to communicate between themselves in order to dynamically exchange information about the networks they can reach and the desirability of the routes available. Routed protocols (such as IP and IPX) are those protocols that can be routed between networks to enable packets to get from one location to another. Routers can run multiple routing and routed protocols. Both RIP and IGRP are distance-vector routing protocols. RIP is the oldest routing protocol and uses only hop count as a metric to determine the best path or route. IGRP is a Cisco proprietary protocol that uses metrics such as bandwidth and delay to determine the best path. It may be desirable for a router network using RIP to convert to IGRP because IGRP has a much higher hop count limitation and uses bandwidth as a metric, thus bringing about better routing decisions when working with an internetwork that has alternative paths. You will console into the router and check the status of the IP routing table and verify the networks that are reachable by each router. You will add IGRP to a router that has only RIP on it and then remove RIP. The ability to apply and interpret routing protocols is essential to maintaining internetworks. Tools / Preparation: Prior to starting the lab, the teacher or lab assistant should have the standard router lab with all 5 routers set up with RIP enabled. Workstations with HyperTerminal should be available to console into the routers. Work individually or in teams. Before beginning this lab you may want to read the Networking Academy Second Year Companion Guide, Chapter 5 - Routing Protocols: IGRP. You should also review Semester 3 On-line Lesson 5. The following is a list of equipment required. Standard Cisco 5-router lab setup with hubs and switches Workstations to connect to the routers Console Cable (roll-over) CAT 5 Ethernet Cable from the workstation to the hub or switch Web Resources: Routing basics General information on routers 2500 series routers 1600 series routers Terms and acronyms IP routing protocol IOS command summary Notes: Step 1. Verify the routers have learned about the other networks in the lab. 1. To display the routing table and see the routing updates that have occurred and the networks the router knows about, issue the following command: router> show IP route 2. What letter appears in the first column of the routing table for any network/subnet directly connected to the router? 3. What letter(s) might appear in the first column of the routing table for any other networks NOT directly connected to the router? (refer to the legend at the top of the display from the show IP route command) Step 2. Determine the directly connected networks. Each router in our lab is directly connected to at least one network, and most routers are connected to 2 or more networks. 1. In the table below, list the networks (class A, B, or C - NOT subnets) to which each router is directly connected (you will be using this information when you enable IGRP). 2. What is the difference between a router's interface address and the attached network address?
> Lab-A |  |  |
> Lab-B |  |  |
> Lab-C |  |  |
> Lab-D |  |  |
> Lab-E |  |  |
Step 3. Determine if there are static routes and remove them. 1. What letter would appear in the first column of the routing table for any network/subnet for which there is a static route? 2. If there any static routes configured on the routers in this lab they need to be removed, since our goal here is for the routers to learn all routes via the IGRP routing protocol. To find the configuration statements for the static routes, issue the following command. Are there any static routes? router#show running-config (notice any command of the form "IP route …", they would be near the end of the output) 3. Enter config mode and remove any static routes with the command: router#config term 4. Remove each of the static routes with a NO command of the form: router(config)#no IP route … (be sure to enter exactly what you found in the show running-config, but with a "no" in front.) Step 4. Routes learned with RIP and IGRP. 1. What letter appears in the first column of the routing table for any network/subnet learned via RIP? Once you have successfully and completely converted to IGRP, each of the entries learned via RIP should be replaced with a similar entry. 2. What will the letter in the first column be when the network/subnet is being learned via IGRP? Step 5. Enable IGRP routing. 1. Issue the following commands: router(config)#router igrp 100 router(config-router)#network a.b.c.d (where a.b.c.d is the actual network address, for example 204.204.7.0) (Add a network statement for each network directly connected to the router being configured; refer to the table you filled in above.) Step 6. Verify that IGRP is now running and configured correctly. 1. Issue the command: Router> show IP protocol 2. At this point, you are still running two routing protocols for IP; RIP and IGRP, and both should be listed. The output includes the administrative distance of the two routing protocols - fill in those values below. RIP: IGRP: Administrative distance is used to choose the routing protocol to prefer when there is more than one in use, with the lowest value being preferred. Since IGRP has a lower administrative distance, it will be preferred. However, if some of the routers in our lab are not yet configured correctly for using IGRP, RIP information will still be learned and used! Continue to issue the command show IP route until there is no more RIP information in the table, and then turn off RIP. Step 7. What is the command to turn off the RIP routing protocol?